The world’s first “freeform” printed house has completed structural testing with 3D-fabrication company Branch Technology and the urban studio of architecture firm WATG. The design and fabrication team, which includes Thornton Tomasetti as structural consultants and mechanical engineers Interface, expects to complete construction on a site at Chattanooga State Community College in Tennessee by early 2019.

The WATG scheme for the house, called “Curve Appeal” for its sinuous contours, was selected from 1,300 entries to a 2016 competition sponsored by Chattanooga-based Branch. The contest’s aim was to showcase the company’s 3D-printing technology, which differs from the usual additive manufacturing process. Instead of depositing layer on top of layer of printing medium, the company’s robot-controlled machines continuously extrude material in a cellular fashion, explains Platt Boyd, Branch CEO. “The printer almost grows the structure,” says Chris Hurst, design director of WATG’s Chicago office.